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A075161 Position of A075165(n+1) in A014486. +0
5
0, 1, 2, 3, 4, 5, 9, 7, 6, 10, 23, 12, 65, 24, 11, 8, 197, 15, 626, 26, 25, 66, 2056, 13, 14, 198, 16, 68, 6918, 29, 23714, 17, 67, 627, 28, 40, 82500, 2057, 199, 27, 290512, 71, 1033412, 200, 30, 6919, 3707852, 31, 37, 38, 628, 629, 13402697, 43, 70, 69, 2058 (list; graph; listen)
OFFSET

0,3

COMMENT

See A075166.

LINKS

A. Karttunen, Alternative Catalan Orderings (with the complete Scheme source)

Index entries for sequences that are permutations of the natural numbers

PROGRAM

(Scheme functions showing the essential idea. For the complete source, follow the "Alternative Catalan Orderings" link:)

(define (A075161 n) (CatalanRankGlobal (parenthesization->binexp (primefactorization->parenthesization (1+ n)))))

(define (primefactorization->parenthesization n) (map primefactorization->parenthesization (explist->Nvector! (primefactorization->explist n))))

Function primefactorization->explist maps 1 to (), 2 to (1), 3 to (1 0), 4 to (2), 12 to (1 2), etc.

(define (explist->Nvector! el) (cond ((pair? el) (let loop ((el (cdr el))) (cond ((pair? el) (set-car! el (1+ (car el))) (loop (cdr el))))))) el)

CROSSREFS

Inverse of A075162. a(n) = A075163(n+1)-1. Cf. A075168.

Sequence in context: A083140 A124652 A048623 this_sequence A029636 A079871 A130064

Adjacent sequences: A075158 A075159 A075160 this_sequence A075162 A075163 A075164

KEYWORD

nonn

AUTHOR

Antti Karttunen Sep 13 2002

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Last modified July 24 12:00 EDT 2008. Contains 142294 sequences.


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